As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING THE MAINTENANCE BASE VISIT FOUND THAT THE INTERIOR LIGHTS FAILED TO ILLUMINATE. THE AIRCRAFT WAS REMOVED FROM SERVICE. REMOVED AND REPLACED THE BATTERY AND CHARGER IAW AMM 33-50-04. THE OPS CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.